At the beginning of Against the Grain, Huysmans says that although Jean des Esseintes always enjoyed the intellectual side of theology, his masters at school never thought of training him for a religious order since his faith always remained "languid." Shut up on his own in the chateau, however, des Esseintes mind keeps reverting to religion, stimulated by the religious subjects of the paintings around him. He vacillates in his views. At one point, Huysmans tells us:
He persisted in considering religion as a superb legend, a magnificent imposture. Yet, despite his convictions, his scepticism began to be shattered.
His Catholic education has not been in vain. Des Esseintes continues to meditate on religious subjects and cannot forget "that poignant and poetic Catholicism in which he had bathed, and whose essence he had long ago absorbed."
Towards the end of the novel, des Esseintes reflects that only the constant companionship of Christians, such as he would find in a religious order, would prevent him from vacillating constantly between belief and doubt:
In the society of well-bred and learned canons, he would have been compelled to share their faith, to refrain from floating between sceptical ideas and transports of conviction which rose from time to time on the water, sustained by recollections of childhood.
However, the canons must be well-bred. Des Esseintes is above all an aesthete and it is his appreciation of beauty in the form of paintings, vestments and even the exquisite manners and learned conversation of Catholics he recalls from childhood that lead him into religious contemplation. Left alone, as he is throughout the novel, he will continue vacillating and focusing on the decorative aspects of religion, using it as a metaphor or a rhetorical embellishment, as he does in the celebrated closing lines of the book:
I shall be in Paris in two days. Well, all is finished. The waves of human mediocrity rise to the sky and they will engulf the refuge whose dams I open. Ah! courage leaves me, my heart breaks! O Lord, pity the Christian who doubts, the sceptic who would believe, the convict of life embarking alone in the night, under a sky no longer illumined by the consoling beacons of ancient faith.